3RRR first commenced broadcasting in 1976 from the studios of 3ST, the student radio station of the Royal Melbourne Institute of Technology (now RMIT University), on an educational licence with the name 3RMT. In 1979 it relocated to Fitzroy, and adopted its present name. During the late 1970s and early 1980s, it became synonymous with the post punk and new wave subcultures. It has developed a devoted base of listeners, many of whom donate their time or money to keep the station going; either as volunteers or through the annual "Radiothon". In late 2004, supporters raised enough money for the station to purchase and move into new premises on the corner of Blyth and Nicholson Streets in Brunswick East after the 20 year lease on their previous studios, in Victoria St, Fitzroy, expired.

3RRR's mission statement was defined in 1990 as "To educate, inform and entertain by drawing upon appropriate community resources. To develop a critical approach to contemporary culture." Triple R's programming is split roughly 70% specialist music and 30% talk-based shows. Hosts have complete autonomy over content and the station does not have playlists. As such, the nature of 3RRR broadcasts varies wildly depending on the time of the week. 3RRR is funded entirely by community sponsorships and public subscribers (currently around 12,000), which, by removing standard commercial pressures, allows this diverse programming.

Due to the reaction from subscribers, in the late 1990s 3RRR cancelled sponsorship deals signed with the Ford Motor Company and music venue The Mercury Lounge (due to its location in Melbourne's Crown Casino). No such "corporate" sponsorship of this type has been considered since. More recent sponsorship includes, for example, Dromana Estate who are "proud sponsors" of Plonk.

With an eclectic mix of programmes and a commitment to independence and integrity, 3RRR has been cited as a model for community radio stations in other cities (such as Sydney's FBi Radio); it has been said that it is a cornerstone of Melbourne's alternative/underground culture. A large number of 3RRR presenters have gone on to work extensively for more commercial radio stations and for the ABC.